The File Shells 



of the left valve. Through the opening made by this marginal 

 angle, the byssus passes out. Length, 4 to 5 inches. 



Habitat. — Norway. 



The Rough File Shell (L. scabra, Dillw.) has its ridged 

 surface set with small pointed scales, and covered with a yellow- 

 ish epidermis. The shell is comparatively thick and ovatie, with 

 the large, anterior ears reflected. Length, 2 to 4 inches. 



Habitat. — Southern Florida, West Indies. 



The Frilled File Shell (L. squamosa, Lam.) has its 

 rounded ridges decorated with erect, flat, scaly plates. The 

 general outline of each valve is obliquely ovate. The ears are 

 small" and depressed, the hinge obHque. Length, i to 3 inches. 



Habitat, — Red Sea, Mediterranean, West Indies, Philippines. 



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